MRMS Reflectivity at -10 C vs. First GLM Flash Centroid vs ENTLN

[19:30 UTC] Convection is well underway in the upper midwest as of this writing with activity beginning to overspread western and southern portions of the Duluth CWA. Decided to take a look at MRMS reflectivity at the -10C isotherm (which is often used as a proxy for initiation of electrification within a developing shower/storm). Although not always the case, previous studies have suggested that the -10C reflectivity of 35 dBZ can be used as a threshold for there to be lightning present within a cell. Certainly there is probably a range that could also be used as a proxy, but for these purposes decided to look for 35+ dBZ on MRMS at the -10C isotherm.

For the developing cell of interest, the first 35+ dBZ on the -10C isotherm appeared at 1830 UTC. 4 minutes later, the first GLM Flash Centroid was noticed with the cell and the first flash event density also appeared. Decided to take a look at the ENTLN ground-based detection as well, and as it turned out, the first cloud flash was detected at the same time the first GLM flash centroid appeared.

 

 Fig. 1: MRMS Reflectivity at -10C isotherm at 18:30 UTC

Fig. 2: MRMS Reflectivity at -10C isotherm at 18:34 UTC

 

Fig. 3: GLM First Flash Centroid Density at 18:34 UTC

 Fig. 4: ENTLN First Cloud Flash Lightning Plot at 18:34 UTC

Rosie Red